Node service child process resolved stale CLI despite systemd PATH override

A Node-based gateway spawned a provider CLI with command name claude. The service-level PATH was changed to prefer a newer standalone CLI binary, but child processes still launched an older CLI from the Node installation directory. The symptom was a headless stream-json provider run that appeared stalled from the gateway/UI, with no parsed progress, while the CLI's own transcript showed activity under the older CLI version.